Brain somatic mutations associated to epilepsy and uses thereof

Abstract

The present invention relates to epilepsy-inducing brain somatic mutations which are associated with intractable epilepsy caused by malformations of cortical development, and uses thereof. More particularly, the present invention relates to an mTOR (Mammalian target of rapamycin) gene having mutations in a nucleotide sequence or an mTOR protein having mutations in an amino acid sequence resulting from the mutations in the nucleotide sequence. Further, the present invention relates to a technique for diagnosing intractable epilepsy caused by malformations of cortical development using the gene or the protein.

What is claimed is: 
     
         1 . An isolated protein consisting of an amino acid sequence which comprises one or more mutations selected from the group consisting of
 substitution of tyrosine (Y) for cysteine (C) at position 1483,   substitution of arginine (R) for cysteine (C) at position 1483,   substitution of lysine (K) for glutamic acid (E) at position 2419,   substitution of glycine (G) for glutamic acid (E) at position 2419,   substitution of proline (P) for leucine (L) at position 2427, and   substitution of glutamine (Q) for leucine (L) at position 2427   in an amino acid sequence of SEQ ID NO. 2.   
     
     
         2 . The isolated protein of  claim 1 , wherein the protein having the substitution of tyrosine (Y) for cysteine (C) at position 1483 is encoded by a gene having substitution of adenine (A) for guanine (G) at position 4448 in a nucleotide sequence of SEQ ID NO. 1,
 the protein having the substitution of arginine (R) for cysteine (C) at position 1483 is encoded by a gene having substitution of cytosine (C) for thymine (T) at position 4447 in the nucleotide sequence of SEQ ID NO. 1,   the protein having the substitution of lysine (K) for glutamic acid (E) at position 2419 is encoded by a gene having substitution of adenine (A) for guanine (G) at position 7255 in the nucleotide sequence of SEQ ID NO. 1,   the protein having the substitution of glycine (G) for glutamic acid (E) at position 2419 is encoded by a gene having substitution of guanine (G) for adenine (A) at position 7256 in the nucleotide sequence of SEQ ID NO. 1,   the protein having the substitution of proline (P) for leucine (L) at position 2427 is encoded by a gene having substitution of cytosine (C) for thymine (T) at position 7280 in the nucleotide sequence of SEQ ID NO. 1, and   the protein having the substitution of glutamine (Q) for leucine (L) at position 2427 is encoded by a gene having substitution of adenine (A) for thymine (T) at position 7280 in the nucleotide sequence of SEQ ID NO. 1.   
     
     
         3 . An isolated gene consisting of a nucleotide sequence which comprises one or more mutations selected from the group consisting of
 substitution of adenine (A) for guanine (G) at position 4448,   substitution of cytosine (C) for thymine (T) at position 4447,   substitution of adenine (A) for guanine (G) at position 7255,   substitution of guanine (G) for adenine (A) at position 7256,   substitution of cytosine (C) for thymine (T) at position 7280, and   substitution of adenine (A) for thymine (T) at position 7280   in a nucleotide sequence of SEQ ID NO. 1.   
     
     
         4 . A composition comprising the protein of  claim 1 ; or an antibody or aptamer specifically binding to the protein of  claim 1 . 
     
     
         5 . The composition of  claim 4 , wherein the antibody or aptamer specifically binds to a region including a mutation in one or more amino acid residues selected from the group consisting of positions 1483, 2419 and 2427 of the protein. 
     
     
         6 . A method for diagnosing intractable epilepsy due to malformations of cortical development, comprising the steps of:
 treating a sample of a patient with an antibody or aptamer specifically binding to the protein of  claim 1  so as to detect the presence of the protein of  claim 1 ; and   determining that the patient has intractable epilepsy due to malformations of cortical development when the protein of  claim 1  is detected in the sample of the patient.   
     
     
         7 . The method of  claim 6 , wherein the antibody or aptamer is able to specifically detect a mutation in one or more amino acid residues selected from the group consisting of positions 1483, 2419 and 2427 of the protein. 
     
     
         8 . A composition comprising the gene of  claim 3 ; or a primer, probe, or antisense nucleic acid complementarily binding to the gene of  claim 3 . 
     
     
         9 . The composition of  claim 8 , wherein the primer, probe, or antisense nucleic acid complementarily binds to a region including one or more bases selected from the group consisting of positions 4447, 4448, 7255, 7256 and 7280 of the gene. 
     
     
         10 . A method for diagnosing intractable epilepsy due to malformations of cortical development, comprising the steps of:
 treating a sample of a patient with a primer, probe, or antisense nucleic acid complementarily binding to the gene of  claim 3  so as to detect the presence of the gene of  claim 3 ; and   determining that the patient has intractable epilepsy due to malformations of cortical development when the gene of  claim 3  is detected in the sample of the patient.   
     
     
         11 . The method of  claim 10 , wherein the primer, probe, or antisense nucleic acid is able to specifically detect a mutation in one or more bases selected from the group consisting of positions 4447, 4448, 7255, 7256 and 7280 of the gene.